关键词:

岱崮地貌,

地貌特征,

河流阶地,

沂蒙山世界地质公园

Abstract:

The Yimengshan UNESCO Global Geopark (UGGp) is the origin of the “Daigu Landform”. Through field investigation of the characteristics of Gu landform, based on the measurement of river valley stratigraphy and profiles, and using the OSL dating of the river terrace to calculate the cutting rate, the formation time of Daigu Landform has been determined. The results show that the geomorphological features of the Daigu Landform are related to the strata lithology of the Gu body. Daigu Landform is a type of mesa structure, with a flat top, steep margin and gentle slope. Gu body is mainly composed of two strata with different lithologies: The top comprises Cambrian limestone with strong weathering resistance but develops many joints, while the Gu body with weak erosion resistance is dominated by mudstone and siltstone. We estimated that the formation time is about 1.77 Ma by using the erosion rate, based on the dating results of the river terrace. The Daigu Landform formation and evolution can be divided into four main stages: (1) the material was formed in the Early Cambrian; (2) tectonic uplift, and the strata gradually exhumed and the shaping stage began; (3) long-term weathering and denudation of various external forces, such as surface water that gradually created the mature Daigu Landform; (4) the landform ended its development when the upper limestone collapsed. The systematic study of the Daigu Landform has great importance in understanding the Daigu Landform and its scientific value, which also contributes to the spreading of geoscience knowledge of UGGps.

Key words:

Daigu Landform,

characteristic,

river terrace,

Yimengshan UNESCO Global Geopark